The present invention relates generally to the field of foundry processing, and more particularly to heat treating metal castings and reclaiming sand from sand cores and sand molds used in the manufacture of metal castings.
Many changes have been made in the field of heat treating of metal castings and reclaiming sand from sand cores and sand molds used in the manufacture of metal castings. Examples of some recent disclosures which address the heat treating of castings, removal of sand cores, and further reclaiming of sand are found in U.S. Pat. Nos. 5,294,094, 5,354,038, 5,423,370, and 5,829,509 (hereinafter sometimes referred to collectively as the "Reference Patents"), each of which is expressly incorporated herein by reference, in their entirety. Those patents disclose a three-in-one process/integrated system that (i) receives and heat treats a casting, (ii) removes sand corelsand mold materials from the casting, and (iii) reclaims sand from the sand corelsand mold materials removed from the casting; the '094 and '038 patents embodying a convection furnace species, the '370 patent embodying a conduction furnace species, and the '509 patent alternately embodying either a conduction furnace species or a convection furnace species (and adding an integrated cooling chamber). The sand core/sand mold materials (referred to hereafter as sand core materials) comprise sand that is held together by a binder material such as, but not limited to, a combustible organic resin binder.
Technology such as that disclosed in the above-mentioned patents are driven, for example, by: competition; increasing costs of raw materials, energy, labor, and waste disposal; and environmental regulations. Those factors continue to mandate improvements in the field of heat treating and sand reclamation.